A spreadsheet-based model (using Microsoft Excel) was developed to assess the amounts and types of habitats within the Malheur National Wildlife Refuge in southeastern Oregon, USA. The Refuge provides critical bird habitat, and the model was designed to quantify the areas of open water, partial water, and water depths during the irrigation season (April–July) from 2021–2024. This data release includes the spreadsheet-based model and any supplemental information that is needed to run the model. Model instructions and results are detailed in the associated USGS report Managing Water for Birds—a Tool for the Malheur National Wildlife Refuge (https://doi.org/10.5066/pending), and users are advised to read the USGS report to understand appropriate use and data limitations. The data release includes a blank version of the spreadsheet model and a polygon shapefile of Malheur Lake that can be used for geospatial analyses. The data release includes rasters that show the proportion of the Malheur National Wildlife Refuge that was open water or partial water (water mixed with vegetation or soil) during each month of the analysis period. The data release includes streamflow measurements collected along the Donner und Blitzen River during 2024.